The effect of sibutramine on energy expenditure and body composition in obese adolescents.

CONTEXT Childhood obesity is now considered to be an epidemic. Drug therapy in this age group remains a topic of research. OBJECTIVE The objective of this study was to examine the effect of treatment with sibutramine (10 mg) on body composition and energy expenditure in obese adolescents. DESIGN The study was conducted as a randomized, double-blind, placebo-controlled trial. SETTING The study was set in an obesity research center. PATIENTS The patients were 24 obese adolescents (age 12-17 yr, 11 boys); four patients withdrew. INTERVENTION Intervention was sibutramine (Meridia) or placebo in combination with an energy-restricted diet and exercise plan for 12 wk, followed by an identical, but medication-free, treatment period (follow-up). MAIN OUTCOME MEASURE Change in body mass index (BMI) sd score (BMI-SDS) was the principal measure of efficacy. Body composition and total energy expenditure were measured by stable isotopes and further calculated according to the four-component model, using underwater weighing and dual x-ray absorptiometry. Basal metabolic rate (BMR) was measured by ventilated hood and adjusted for sex and body composition (BMRadj). RESULTS After intervention, the decrease in BMI-SDS was comparable in both groups. During follow-up, BMI further decreased in the placebo group but stabilized in the sibutramine group. Changes in the percentage of fat mass were not different between both groups. BMRadj decreased in the placebo group and remained constant in the sibutramine group. During follow-up, BMRadj decreased in the sibutramine group and increased in the placebo group. Changes in total energy expenditure were not significantly different. CONCLUSION The effect of sibutramine on BMI-SDS was not significant. Sibutramine may diminish the decrease in BMRadj associated with energy restriction in obese adolescents.